The Early Bird
by Jill-in-the-Box
Summary: As Demming embarks on a relationship with Beckett, he gets a few hints that Castle plays a bigger role in her life than he initially thought. Three one-shots, set during 2x23 and 2x24.
1. Something New

**Disclaimer: **I don't own Castle and don't profit from writing these stories (except for my own amusement).

**SOMETHING NEW**

It takes Demming a moment to figure out where he is on the first morning he wakes up in Kate's bed. It's at least several weeks sooner than he might have expected based on how conservative he's assumed her to be. He just figures it's been a while since the last guy; the thought is more than a little flattering.

Kate is just getting out of the shower, smelling more like cherries than ever and wearing a short bathrobe that shows off her long legs. He can't help staring at her.

"What?" she says. "Never seen a woman in a bathrobe before? I know all about your community service record, but you can't be _that _much of a goody-goody."

He chuckles, relieved that things aren't awkward between them at all.

Her eyes shift from his face to the nightstand. She quickly snatches something from the wooden surface, and he catches a brief flash of gold. He vaguely recalls her taking off a chain from around her neck last night, but he was too distracted to remember what was hanging from it.

She crosses over to her dresser and carefully puts whatever she's holding away. He turns his attention to the nightstand and the stack of books on top of it. One of them catches his attention; its cover isn't wrapped in plastic and doesn't have a library code on the spine. He carefully pulls the book from the middle of the pile. It's a newly bought book, some classic of Russian literature that he's heard of but never actually read. He opens it. On the inside front cover is a handwritten message. _Kate, I remember seeing this on your bookshelf. It's one of my favorites and I thought it would be a good place to start rebuilding your collection. Happy reading and stay safe. Rick Castle._

He feels a stab of jealousy as his imagination runs through several less-than-innocent scenarios for why Castle would have access to Kate's bookshelf. He reassures himself remembering Castle's own words. _Me and Beckett? No!_ It's as if the man had never even considered the possibility.

He focuses on Kate now, still facing away from him and rummaging through what looks like a jewelry box. Her hair is still damp and it's wavy. He's known in the back of his mind that her hair isn't naturally straight—he remembers when they were kickboxing, it started to curl as soon as she'd started sweating. He likes it; it makes her look more like Kate than Detective Beckett.

Kate must be able to sense people watching her, because she turns around and shoots him a puzzled look. "What're you staring at?" she wants to know.

To his surprise, all he manages to squeak out is, "Your hair. It's curly."

"Excellent observation, Detective Demming," she laughs. "Keep up the good work, and we may recruit you to Homicide."

"That would be nice," he says. "Unlimited access to amazing coffee and pretty lady detectives."

She giggles at that. "Humans have finally discovered a flaw in Tom Demming. He makes up the cheesiest lines _ever_."

He winces. It _was_ pretty cheesy. "The curls look good on you though. You should try it at work," he suggests. Suddenly concerned that she could take it as an insult to her current appearance, he quickly adds, "I mean, only if you want to. You look fine the way you wear your hair now."

She dismisses his worry with a wave of her hand. "I change my hair all the time," she tells him. "I had bangs when I first met Esposito. Then this weird layered cut when Ryan came. And," she continues, as she twirls a curl around her index finger, "I had short hair when Castle first started working with us."

_Huh. _Judging by how long Kate's hair is now, Castle's been with them for a lot longer than it might take for a simple research project. His mind drifts off to consider the growth rate of hair, and by the time he's listening to her again, he hears, "… so I guess it's time to try something new."

"Great," he agrees with a smile.

_Something new_ lasts until a little while after the Wilder case is wrapped up. He's eating lunch with Kate's team and Castle. All of a sudden, Castle remarks that her hair looks like someone named Jenny's, then proceeds to compliment Demming's tie. Demming doesn't get the joke, but everyone else in the room obviously does, because Esposito chortles out loud, Ryan glares at Castle, and Kate blushes ever so slightly and rolls her eyes in a way that makes her look absolutely _adorable_.

The next time he sees her, her hair is straightened again.


	2. Flags on Plays

**Disclaimer:** I don't own Castle and don't profit from writing these stories (except for my own amusement).

**FLAGS ON PLAYS**

He and Kate quickly settle into a routine. He's gotten used to waking up at her impossibly early hour. He keeps a work week's supply of shirts and ties in her closet, right next to the four or five blouses she has in the same style but different colors (_they were on sale_ was her answer when he asked about it). His bar of soap sits next to her cherry body wash in her shower caddy (his partner had given him a strange look on the first and last morning he used it). They share a cab to work (she always insists on paying her half of the fare). He takes his coffee breaks in the Homicide break room and eats his lunch with her in one of the Homicide meeting rooms. At the end of the day, he goes upstairs to pick her up and they take a cab back to her place again. They either order in or, if they're feeling adventurous, they try to whip something up from whatever is still edible in Kate's fridge. On weekends they take walks in the park (which she likes) and go grocery shopping (which she doesn't). On their nights off he'll sit on one end of her couch drinking a beer and watching whatever sports event happens to be on, while she'll be curled up against him with one of her library books and a glass of wine.

It's nice, he thinks, having someone to go home to, especially when it's someone like Kate. Kate is smart and funny and beautiful and just plain amazing, and he can't help wondering whether he's going to find out that there's some sort of catch.

* * *

She's set boundaries, of course. She's spelled out clearly that they're not supposed to talk about this _thing _between them to their colleagues. True to his word, he doesn't, although he suspects Esposito and Ryan already know. Esposito looks at him appraisingly, as if he's trying to decide whom he should side with should things fall apart. Ryan watches him with barely concealed amusement, as if he's watching some incredibly ridiculous chick flick he's been dragged to by his girlfriend. (As it turns out, Kate doesn't like chick flicks. She does, however, like con movies.)

Beyond that rule, Kate makes her own efforts to hide the fact that they're seeing each other. In the mornings she'll get out of the cab several blocks before they get to the precinct. She always claims that she needs the exercise or she wants to buy some breakfast from the bakery down the street, but he knows she doesn't want to be caught walking into work with him. When he comes upstairs in the evenings, she'll stall until it looks like there's no one watching them leave together. She won't eat off his plate at lunch and she'll step away when he stands too close when they're making coffee. Her need for privacy is one of the most frustrating things about their relationship.

But it's not the most frustrating thing. That honor belongs solely to one Richard Castle.

What was the guy's problem, anyway? Apparently, _no flag on the play _had not excluded the possibility of being tackled at every move. Constantly trying to one-up him on the Wilder case, making cracks about how Robbery detectives weren't qualified to investigate homicides, and basically just acting like an overgrown ten-year-old around Kate…

As any good detective should, he's done his research. He's found out from Esposito that Castle's been around for more than fourteen months, except for some sort of break during summer (he wishes fervently that there will be another extended vacation this year). He's read the blurb in the eligible bachelor article in the _Ledger _(he wonders whether Kate saw it, and wonders what happened to Castle if she did). He's also looked at the plot synopsis of _Heat Wave _on Wikipedia. He never asks, but he wonders if Kate has read _Heat Wave_. He guesses she probably has, and not the Wikipedia version either; it's dedicated to her and _all my friends at the 12__th_, after all. Demming guesses that he would not be considered a friend at the 12th.

The worst part is that he can't create a proper plan of attack without knowing his rival's motivations, and truth be told, he can't figure out what Castle's intentions toward Kate are. Was he just a friend with an overactive imagination and a pathological need for her undivided attention? Did he see her as some sort of conquest? Was he in love with her?

Maybe it doesn't matter what Castle wants, Demming decides. He just wants Castle to _go away_. Which is why on the first night of the Wilder case, he steps between the two of them and says _you ready? _just loud enough for Castle to hear.

He expects Castle to get the hint and back off. But no. The man probes further, forcing Kate to awkwardly stammer out some excuse about sharing a cab.

There's an icy silence as they ride the elevator downstairs, as they wait on the curb, as they ride back to her place. He wants to ask her what the big fuss is about; he hasn't technically broken any rules; after all, Castle isn't one of her coworkers, just a guy who's following them around. But if he's learned one thing about women, it's that you _never _try to justify your actions when they're angry with you. _Ever_.

When they reach their destination, Kate gets out first and doesn't look too surprised when he doesn't follow. "Night," she says curtly, tossing her half of the fare onto the seat next to him.

"Night," he replies.

His initial plan is to wait until tomorrow to see if she's calmed down, but as soon as he climbs into bed he sees one of _her _books next to him, and the next thing he knows, he's reaching for the phone.

"Hey," Kate says, when she picks up the other line. Her voice is neutral, neither bitter nor pleased to hear him.

"I'm sorry if I embarrassed you," is the first thing out of his mouth.

She sighs. "At least it wasn't Montgomery or the guys," she mumbles. She says nothing to indicate that she's accepted his half-apology.

"I know that wasn't how you wanted Castle to find out about us," he adds softly.

There's a long pause before she says, "He already knew."

"How do you know?"

"He called you my boyfriend."

He's taken aback by that response; he'd thought that being her boyfriend was a given. Now he has to know. "Well, am I?"

She doesn't answer, and he mentally slaps himself for being so pushy when she's cross with him. There's another awkward pause before she says, "It's late. We've got a long day tomorrow."

"Yeah. Okay. See you."

"Night."

* * *

The next morning he comes in, armed with coffee and a blueberry muffin for Kate. She's not there yet, but Castle is.

"Good morning," Demming says, as politely as he can manage.

Castle doesn't respond in kind but instead asks, "What's in the bag?"

"Breakfast for Beckett," he replies.

Without asking, Castle reaches for the bag and peeks in. "She doesn't like blueberry muffins," he says.

"Okay, what does she like, then?"

"Bearclaws, of course," Castle says, as if speaking to a child. He turns his attention to the cup of coffee. "Is this sugar-free?" he wants to know.

Demming feels like he's in Spanish 205 again, being quizzed on verb conjugation in front of the whole class. "What? Sugar-free? She doesn't need to be on a diet!"

"No," Castle explains, "but if she has too much sugar, she'll crash in the middle of the morning and be cranky for the rest of the day."

Demming is starting to get a little cranky, and it has nothing to do with the amount of sugar in his coffee.

When Kate finally arrives, she smiles her thanks at him as she picks up his peace offering, but she sets it down after a single bite. Castle wolfs the rest of the muffin down with a smug smile in his direction. Kate gets a look on her face like she's about to give Castle a lecture but doesn't.

At the end of the day, Demming doesn't dare follow Kate when she says her goodbyes and leaves the room. Instead, he spends an awkward fifteen minutes pretending to read the file and feeling Castle's eyes on his head, until Castle breaks the silence and offers to share a cab with him. He's not sure if it's a jab or a ploy to make sure he doesn't go to Kate's, decides it's a little bit of both, and takes his own cab home.

* * *

When the case is finally wrapped up, he finds Kate in the back room processing the charges. He can't help feeling proud; Castle might know her favorite breakfast, but only a detective would know exactly where a detective would be when the crime was solved.

"Can I have a minute of your time?" he asks, and she follows him into the hall and raises her eyes to look at him. He knows exactly what he needs to say to get back into her good graces, and he knows that she's worth swallowing his pride for a moment.

"I really want to apologize for the other night," he tells her. "You've worked very hard to earn everyone's respect, and I'll do everything I can not to compromise that."

The expression on her face softens. "Thank you," she says with a nod.

He continues, "I know I acted like a kid. This is no excuse, but the way Castle acted around you got me a little jealous and I overreacted."

"Don't worry, it's perfectly normal behavior for him. He goes after anything that moves."

She's not joking or playful when she says it; he can almost taste the unusually sharp sting in her tone. Carefully, he steers back to the task of making up. Tentatively reaching out his hand, he says quietly, "So, we're good?"

Kate's fingers meet his halfway. Before he can register what's happening, to his complete surprise, she's leaning in and kissing him. Breaking all of her own rules, right there in the middle of the hallway, where Esposito or Ryan or even her _boss_ might see them. It's completely out of character, he thinks, for this reserved, no-nonsense woman he's come to know. He can only conclude that Kate must be one of those people who go out of their way to forgive those who are humble enough to give a proper apology.


	3. Pancakes, Plans, and Partings

**Disclaimer:** I don't own Castle and don't profit from writing these stories (except for my own amusement).

**PANCAKES, PLANS, AND PARTINGS**

When he opens his eyes that Sunday morning, Kate is still asleep. He slips out of bed and heads into the kitchen, determined to make the most out of the first time he's woken up before she has.

He rummages through her cupboards and refrigerator, gathering the ingredients for pancakes. She has one less egg than the recipe calls for and he can't find vanilla anywhere, but he mixes the batter anyway, and by the time he hears her footsteps in the hall, he's already starting the first batch.

"Pancakes?" she says, looking equal parts sleepy and confused.

"Esposito once told me that they're an edible way of saying thank you so much for last night," he replies.

She finally smiles. "Well, in that case, you owe me at least a dozen more pancake breakfasts."

"Or maybe you owe me," he teases back. "I don't even _like _baseball."

That one earns him a laugh. They fall into a comfortable silence until he suddenly senses Kate staring at him a little too intently, watching his every move as he flips the pancakes. "What's with the serious face?" he prods. "Was one of your ex-boyfriends a fan of pancakes too?"

There's a pause before she says, "Nah. Just doughnuts with rainbow sprinkles."

It's his turn to laugh, even though it's so ridiculous that he can't quite decide whether or not she's joking. After another moment of quiet, he ventures, "I was thinking. Memorial Day weekend. My family has a beach house in Asbury, but no one's using it this year. I was hoping you'd come out there with me."

Kate's face lights up at the mention of the beach. "I'd love to," she agrees enthusiastically.

"And there's a great Chinese place just around the corner. On Friday nights they have an amazing seafood buffet. Ten times better than Hung's. It's almost impossible to get a reservation this close to the day, but we can try."

She bites her lip as she takes the now-empty batter bowl to the sink and begins to wash it. "I don't know about that. I was hoping to work on Saturday," she tells him. "I'm running low on vacation days from apartment hunting, and my cousin's getting married in L.A. this fall, and I promised I'd be there."

"Oh," he says. He wonders if she'll ask him to come with her, and makes a mental note to check on how many vacation days he's got saved up. "Bridesmaid?"

"Yeah. Seventh time," she says as she reaches for a dishtowel.

"Popular you," he jokes. "Have you ever _not_ been a bridesmaid?"

"Only once, actually, now that I think about it," she answers, pausing in her drying of the bowl to smile at the memory. "It was a small wedding. I caught the bouquet, too." She stops suddenly, looking embarrassed.

He's quick to reassure her. "Don't worry. I know you weren't trying to send any coded messages or anything," he tells her. She nods and smiles, and he laughs at her expression of relief. "Goodness, Kate, relax. Not every guy has a mental breakdown at the mere thought of commitment."

The smile vanishes in an instant. He has absolutely no idea what he's said wrong, so he decides a change of subject is his best course of action. "So. Check on your vacation days for next weekend. Worst case scenario, you take the pay cut and I'll help you sell off some of your ridiculous overcoats."

She swats at his arm with the dishtowel she's holding.

* * *

Thanks to a sudden spike in robberies, he doesn't see her at all for the next few days. On Monday and Tuesday, he works nonstop past eleven and she's already gone when he comes upstairs. When the tide of work finally seems to abate by Wednesday, Kate and her team catch a case. He talks to her briefly on the phone that night, and she manages to stay awake for a few minutes to fill him in on the details—some crazy spy game that sounds like something Castle might have invented. (Why is he thinking about Castle, anyway? It's not healthy.)

On Thursday morning, he sets his alarm early and gets to the precinct by 7:30. He's not surprised at all to see her already there. She looks so stunning, perched on top of her desk and reading from a file, and he hasn't seen her in so long, that he decides he'll risk her anger. He wastes no time in striding over to her, snatching the folder from her hands, and burying his face in her neck.

"What the _hell_?" Kate hisses, but he can tell from the way her body tenses and her breathing quickens that she's enjoying this more than she wants to.

"I missed you," he whispers. "Can I see you tonight?"

He feels her nod. Before either of them can say anything more, her head whips toward one side. He turns to look, and sees Castle, of all people, parading in. At 7:35 in the morning. What the _hell? _It's as if the guy _knew _he'd be here and was trying to sabotage his moment with Kate or something.

Kate hurriedly slides off the table and he barely manages a polite nod at Castle as he walks by, all the while thinking about using Kate's kickboxing moves on the man.

It's the first time that morning that Richard Castle pisses him off.

The second time comes at half past ten, after the restaurant in Asbury calls him about an opening for Friday dinner. He races upstairs to tell her. The first thing he sees his Castle, looking a little too comfortable in front Kate's murder board and sitting a little too close to Kate, as if he owned the 12th precinct, as if he owned _her_.

He decides in that moment to not-so-subtly inform Richard Castle exactly how and with whom Kate Beckett spends her three-day weekends. He knows she'll be furious later, but he's pretty sure the wounded look he sees on Castle's face is totally worth it.

* * *

When he comes upstairs to pick her up that night, he's expecting either the cold shoulder or a rant about how he's compromised her professional image. She's upset, he can tell, but to his surprise it's not the angry type of upset. It's… sadness.

She's quiet in the cab and gives unusually vague answers when he asks what's wrong. He runs through possible scenarios in his mind. A particularly disturbing case? A death in the family? He doesn't know.

He doesn't push her that night and she ends up making the first move, but she's so detached and subdued that he almost feels as if he's committing a crime. The next morning he's up before she normally is, but she's already gone. In her place is a note weighted down by a key. _Had an idea about the case & going in early to look into some leads. Lock up behind you. _The optimist in him wants to interpret the key as a signal of some sort of progression in their relationship, but he knows it probably just means she trusts him more than the criminals who might loot an unlocked apartment.

Sometime in the middle of the afternoon he decides he should head upstairs to see her. He's got his coffee mug in hand and is on his way when his partner, Charlie Robertson, demands, "Where are you going?"

"Coffee," he says, holding the mug up in exasperation.

"Break room's the other way," Robertson points out. The guy's even nosier than Castle.

"Okay, fine," Demming snaps. "I'm going upstairs for coffee. Is that a problem?"

"Making excuses to watch Beckett and Castle?"

Demming nearly drops his mug. "What?" he sputters, wondering exactly how much his partner knows.

"Beckett and Castle," Robertson repeats, as if it is the most obvious thing in the world. "You know, Nikki Heat and the guy who wrote the book?"

"Yeah, I know who Beckett is. I worked the Racine case with her, remember?"

His partner nods and shrugs. "I guess most of it happened before you got here, but we used to make excuses to go up to Homicide and watch them at their old-married-couple act and get inside information for our bets."

"Bets?"

"Lanie the ME had this pool going. Almost everyone here made bets on when they'd get together. Except maybe her boss."

"Had a pool? Did anyone win?" Demming asks, and instantly senses that spoke a little too quickly.

Robertson notices it too, and raises an eyebrow. "Why do _you _care, anyway? Are _you _dating her? Is that why you've been going up there all the time?"

"No! They have good coffee up there." Robertson looks skeptical. "Come on. I'll show you."

* * *

When he's finally face-to-face with Kate later that afternoon, she dives straight into _we need to talk _and _I don't think I'll be going to the beach house with you this weekend_. He's been on the receiving end of this speech enough times that he knows exactly what she means.

He asks her for a reason, looking for something he can try to fix. _You know better than to kiss me at my desk_ (but I missed you). _Don't think you can bring your Robbery friends up to my floor just because you're dating me_ (but I was trying to keep us a secret like you wanted). _You shouldn't have dragged my private life in front of Castle_ (but he's trying to steal you away from me).

But all Kate says is _you're not what I'm looking for right now_, and for the first time, Tom Demming realizes that Castle's had her all along.

He leaves her key on her desk on the way out.

* * *

As he's leaving for the day, he steps on the elevator (_without her_) to see Castle standing there with his arm around a gorgeous blonde (not as beautiful as Kate).

He tries to take some twisted pleasure in this fact, tries to tell himself that it's Kate's fault they're both going to be miserable this summer, tries to tell himself that she had it coming.

For some reason or another, he can't quite bring himself to believe it.

**FIN.**


End file.
